Dream

So I get this PM from someone and they say that i'm asking for trouble wiring an OBD2 Ecu and such in an OBD1 Car. Is this true? Am I really getting into that much trouble? I dont think the person who PMed me has done it before and of course I want someone that HAS done it before to answer.

Thanks.

For reference: Im putting an HX motor and ECU in my 92 CX Hatchback.

TeamNextGenChris

i've never converted an OBDI car to OBDII,but i can tell you your easiest bet is to put the motor in there and use the appropriate OBDI ECU.
Chris

reaction360

use an obd1 engine harness and ecu. will make your install easier. some of the sensor plugs may be different, so keeping both harnesses on hand will be a good idea.

Status Sean

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by reaction360 &raquo;</TD></TR><TR><TD CLASS="quote">use an obd1 engine harness and ecu. will make your install easier. some of the sensor plugs may be different, so keeping both harnesses on hand will be a good idea.</TD></TR></TABLE>

thats how its done !

B18C5-EH2

The only problem you're looking at is that the HX engine has no equivalent in 1992-1995, so finding a good OBD1 ECU for it might be tricky.

You should use the OBD1 stock Civic engine harness, alternator, injectors, and a P28 ECU if that will even work.

Also there will be two wires on the HX distributor that need to be repinned because the HX distributor has one plug while the 1992-1995 Civic engine harness has two plugs.

It's a very easy thing to do as evidenced by my pics:





Also you'll need to keep your alternaor off your stock engine because the plugs are different. There is a a way to use the HX one since it's newer, but it requires taking the voltage regulator out of the OBD1 one and putting it into the HX alternator so it will plug in since the plugs are part of the voltage regulator.

Also why the need for the double post?

https://honda-tech.com/zerothread?id=745509

I answered your Q in that topic too...

Spade

The HX needs a VTEC cross over at 2700-3000. Otherwise, you will have serious power issues due to the econimical design of the cam.

B18C5-EH2

Also before anyone jumps me saying that the 1992-1995 VX is the same as the HX, I don't think they are identical enough to run the HX engine off of a VX ECU.

The VX ECU looks for a 5-wire o2 while I think the HX engine uses a 6 wire. I'll double check that...

I think the P28 will be decent, but I'd always wonder if it was running right.

B18C5-EH2

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spade &raquo;</TD></TR><TR><TD CLASS="quote">The HX needs a VTEC cross over at 2700-3000. Otherwise, you will have serious power issues due to the econimical design of the cam.</TD></TR></TABLE>

I'm thinking P28 1992-1995 Si/Ex ECU and a V-AFC for fine fuel tuning and VTEC X-over.

Spade

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18C5-EH2 &raquo;</TD></TR><TR><TD CLASS="quote">

I'm thinking P28 1992-1995 Si/Ex ECU and a V-AFC for fine fuel tuning and VTEC X-over.</TD></TR></TABLE>

That will work.
With the HX, id only go with the HX ECU but that also will require the 5 wire O2 sensor!

B18C5-EH2

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spade &raquo;</TD></TR><TR><TD CLASS="quote">

That will work.
With the HX, id only go with the HX ECU but that also will require the 5 wire O2 sensor!</TD></TR></TABLE>

And a crank fluctuation sensor, extra o2 sensor, blah blah...

And a $150.00 or more OBD1 to OBD2 jumper harness.

Spade

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18C5-EH2 &raquo;</TD></TR><TR><TD CLASS="quote">

And a crank fluctuation sensor, extra o2 sensor, blah blah...

And a $150.00 or more OBD1 to OBD2 jumper harness.

</TD></TR></TABLE>

Exactly. Expensive.

But to do the P28 you must have the VAFC.

HX = not the greatest choice.
See if you cannot get a Z6 head to throw on there!

EE_Chris

Told ya' so.

But like I had said, more trouble than its really worth to stay OBD2 with thing for reasons mentioned above.

Good luck though if you try it.

reaction360

oooh...i didnt notice that "HX motor" part of the post. i'd also recommending gettting an ex motor. I think the cam is different from the ex's as well.

Dream

Headache.

b18 -- Hey I asked again because I was looking for a more in depth answer, so thanks for taking the time to post. APpreciated.

I really want to do this HX swap, but honestly if it's all that much trouble then it's a bit discouraging.

You can't use the p28 because of all this other stuff...

I might just give in and do the over done z6 or y8 turbo.

Concerning using a VAFC to change the vtec c/o point... If I did use a p28 to stay obd1... would this affect anything else other than the actual Vtec part? Because if it'll work just perfect with obd1 and VAFC.. hell im using a VAFC ANYWAY to run my hack so how's that sound?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Quote, originally posted by B18C5-EH2 »
And a crank fluctuation sensor, extra o2 sensor, blah blah...

And a $150.00 or more OBD1 to OBD2 jumper harness.



Exactly. Expensive.

But to do the P28 you must have the VAFC.

HX = not the greatest choice.
See if you cannot get a Z6 head to throw on there!</TD></TR></TABLE>

Would I need all of this if I used p28 and a VAFC and run it on Obd1?

TeamNextGenChris

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dream &raquo;</TD></TR><TR><TD CLASS="quote">Headache.

b18 -- Hey I asked again because I was looking for a more in depth answer, so thanks for taking the time to post. APpreciated.

I really want to do this HX swap, but honestly if it's all that much trouble then it's a bit discouraging.

You can't use the p28 because of all this other stuff...

I might just give in and do the over done z6 or y8 turbo.

Concerning using a VAFC to change the vtec c/o point... If I did use a p28 to stay obd1... would this affect anything else other than the actual Vtec part? Because if it'll work just perfect with obd1 and VAFC.. hell im using a VAFC ANYWAY to run my hack so how's that sound?</TD></TR></TABLE>
i know this doesn't answer your question,but are you wanting to swap in the HX motor for performance?i was under the impression at first that you just needed a replacement motor,and has access to an HX setup.there's a reason there are way more Z6 and Y8 swaps out there-they're a much better performance platform than the economy minded HX and VX motors.just seems like a lot of work when there are better options that will be an easier install.
chris

Dream

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">i know this doesn't answer your question,but are you wanting to swap in the HX motor for performance?i was under the impression at first that you just needed a replacement motor,and has access to an HX setup.there's a reason there are way more Z6 and Y8 swaps out there-they're a much better performance platform than the economy minded HX and VX motors.just seems like a lot of work when there are better options that will be an easier install.
chris </TD></TR></TABLE>

I agree with you on what you said. There are alot of z6 and y8's out there. But I dunno, it's just this itty bitty challenge of an HX that maks me really want to get it. It's convenient also...

For 400 the guy is selling me:
d16y5 with 68k
d16z6 tranny in good condition
p28 ECU
Axels
Motor mounts
d16z6 intake manifold and throttle body
d16z6 Exhaust Manifold and d16y5 Exhaust manifold.

I already have a VAFC sitting on my desk.... it's just screaming for me to buy it and not only that.. I know if I wanted too.. I could tell him to give it to me for like 300.

I just want to find out what I can and can't do.. I plan on Turbo Charging it for sure.

TeamNextGenChris

sounds like you have a good start for your project..but,honestly,all you need is a Z6 or Y8 bare long block and you're set to go.you could sell the HX long block for a good chunk to put down towards the Z6/Y8....i just really think you're not going to be satisfied with that setup.i have a Z6 in my 93 DX hatch with exhaust and CAI(used to have header too),and i'm barely satisfied at most with the power it makes.i'm either turboing it or swapping to an LS/B20.and this is just my daily driver-i can't imagine having less power than this(i thought i was going to die with the stock D15).
just my $.02

s2000june

im stuck in the same boat man
i got a 92 vx hatch
and i wanna put my 00 ex motor in d16y8
i can do but i dont wanna do untill i know everything i gotta switch..
i have obd 1 dist from a ex
i have p28ecu
i have obd1 alt.
and i have my stock harness in the car now
and i have the ex harness
so i dunno whats left. or what exactly i gotta do besides ripin the dist.

TeamNextGenChris

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by civicrida3 &raquo;</TD></TR><TR><TD CLASS="quote">im stuck in the same boat man
i got a 92 vx hatch
and i wanna put my 00 ex motor in d16y8
i can do but i dont wanna do untill i know everything i gotta switch..
i have obd 1 dist from a ex
i have p28ecu
i have obd1 alt.
and i have my stock harness in the car now
and i have the ex harness
so i dunno whats left. or what exactly i gotta do besides ripin the dist.</TD></TR></TABLE>
sounds like you're ready to go.if you have an OBDI EX distributor you won't have to repin it.with that and the OBDI alternator you should be plug and play.
chris

Dream

Well there's not enough info around. This is the most i've found and it's just theories though.

I don't have a problem with repinning Dizzy's and I can get the y5 distributor since this one i'm buying has a z6 on it.

Im really going to try it though. There just isn't enough info and if I try it, there'll be something out there for others who want to know what you can and can't do with the motor.

TeamNextGenChris

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dream &raquo;</TD></TR><TR><TD CLASS="quote">Well there's not enough info around. This is the most i've found and it's just theories though.

I don't have a problem with repinning Dizzy's and I can get the y5 distributor since this one i'm buying has a z6 on it.

Im really going to try it though. There just isn't enough info and if I try it, there'll be something out there for others who want to know what you can and can't do with the motor.</TD></TR></TABLE>
trying something different gets my approval
bottom line-if you're not happy,all you do have to buy is a Z6/Y8 longblock as you've already got all the other parts you need.
good luck
chris

Dream

Thanks for the wish good luck man. Hopefully i'll get something positive out of it and if not, well I tried it.

Can anyone answer this or shed more light?:

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Concerning using a VAFC to change the vtec c/o point... If I did use a p28 to stay obd1... would this affect anything else other than the actual Vtec part? Because if it'll work just perfect with obd1 and VAFC.. hell im using a VAFC ANYWAY to run my hack so how's that sound?

</TD></TR></TABLE>

EG6-DC2

First of all, this is the most annoying thing to me, is that YOU DON'T NEED AN OBD1 HARNESS TO PUT AN OBD2 MOTOR IN AND OBD1 CAR! I had a 2001 GSR motor in my '93 SI didn't add any wires, change any wires, nothing and had no problems at all (but I was running a chipped B17 computer - hence not having to wire up the secondary butterflies) Second of all, you can't use and OBD2 Civic harness in an EG cause it goes all the way to the ECU, unless you are planning on converting the whole car. So you will have to use your wiring harness unless you can get a VX on cause like someone said I do believe you will have to run a 5-wire O2 sensor. Third, I personally wouldn't go through all the trouble of swapping in an HX motor, I would go with a Z6, Y8, or D15B7-(I believe), if you want a cheap swap, with soem good potential. Also don't flame on me cause I am new and you think I don't know what I am talking about.

Dream

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">For 400 the guy is selling me:
d16y5 with 68k
d16z6 tranny in good condition
p28 ECU
Axels
Motor mounts
d16z6 intake manifold and throttle body
d16z6 Exhaust Manifold and d16y5 Exhaust manifold</TD></TR></TABLE>

Is 400 not cheap enough?

Im not saying anyone is WRONG about the z6 or y8 or even JDM d15... but the real reason everyone is saying that is because someone else experienced it and passed down the knowledge.

There isn't alot here on the y5 and, for three whole days of frustrating research, there isn't alot on the net period.

So what better way to find out about it than personal experience?

And I didn't understand... this part of your post:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">First of all, this is the most annoying thing to me, is that YOU DON'T NEED AN OBD1 HARNESS TO PUT AN OBD2 MOTOR IN AND OBD1 CAR!</TD></TR></TABLE>

DId you mean to tell me that I DON"T need an obd2 harness in my obd1 car? Lost me there.

And if I'm using my VAFC and all Obd1 parts including an obd1 dizzy.. ( if that's possible, still lost on that part. ), then would I need a 5-wire 02?

Again i'm inquiring.. I have no experience with obd2 anything.. only z6 and y8's.

EG6-DC2

What i was trying to say was that most people say is that if you have an OBD2 motor (complete including wiring and all) then you have to switch it back down to an OBD1 wiring harness, dizzy, alter. etc... in order for you to put it in an OBD1 car and that is crap, cause liek i said i just plugged and played a 2001 GSR motor in my '93 Si. Another thing I forgot to mention was that I think that someone makes an OBD1 to OBD2 ECU jumper, so you can run that HX ECU and not have to find one. Also the 5-wire is because it is a VTEC-E motor and I am not 100 percent sure but i believe it gives a more true reading.